<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <div id="app">
        <select @change="fn1" id="" ref="sele1">
            <option value="">请选择</option>
            <option v-bind:value="index" v-for="item,index in pro">{{item}}</option>
        </select>
        <select @change="fn2" ref="sele2" name="" id="">
            <option value="">请选择</option>
            <option v-bind:value="index" v-for="item,index in city[pronum]">{{item}}</option>
        </select>
        <select ref="sele3" name="" id="">
            <option value="">请选择</option>
            <option v-bind:value="index" v-for="item,index in zoom[pronum][citynum]">{{item}}</option>
        </select>
    </div>
</body>
<script src="../../static/vue.js"></script>
<script>
    new Vue({
        el: "#app",
        data: {
            pro: ['广东', '江苏', '山东'],
            pronum: 0,
            city: [['广州', '深圳', '东莞', '佛山', '珠海'], ['南京', '苏州', '无锡', '常州', '徐州'], ['济南', '青岛', '烟台', '潍坊', '临沂']],
            citynum: 0,
            zoom: [[['天河区', '海珠区', '越秀区', '荔湾区', '番禺区'], ['福田区', '南山区', '罗湖区', '宝安区', '龙岗区'], ['东城区', '南城区', '莞城区', '南城区', '香洲区']], [['玄武区', '白下区', '秦淮区', '建邺区', '鼓楼区'], ['姑苏区', '吴中区', '相城区', '虎丘区', '吴中区'], ['崇安区', '市中区', '濠江区', '奎文区', '潍城区']]]
        },
        methods: {
            fn1(){
                console.log(this.$refs.sele1.value);
                this.pronum=this.$refs.sele1.value
            },
            fn2(){
                console.log(this.$refs.sele2.value);
                this.citynum=this.$refs.sele2.value
            }
        },
    })
</script>

</html>